Mechanical gyroscopes are used to determine direction of a moving vehicle platform based upon the sensed inertial reaction of an internally moving proof mass. A typical electromechanical gyroscope comprises a suspended proof mass, gyroscope case, pickoffs, drive and sense electronics. The inertial proof mass is internally suspended from the gyroscope's case that is rigidly mounted to the moving vehicle platform and helps determine the inertial motion of the platform while otherwise isolating the proof mass from external disturbances. The pickoffs to sense the Coriolis forces on the proof mass, the force rebalance electrodes to maintain or adjust this motion and the readout electronics that must be in close proximity to the proof mass are internally mounted to the case which also provides the electrical feed-through connections to the platform electronics and power supply. The case also provides a standard mechanical interface to attach and align the gyroscope with the moving vehicle platform. In various forms gyroscopes are often employed as a critical sensor for vehicles such as aircraft and spacecraft. They are generally useful for navigation or whenever it is necessary to autonomously determine the orientation of a free object.
US Patent Publication 20070017287, “Disc Resonator Gyroscopes,” describes embodiments of a disk resonator gyroscope (DRG) as does U.S. Pat. No. 7,581,443, where a resonator layer is bonded to a Si substrate and then etched with deep reactive ion etching.
It is known to make a MEMS quartz resonator for a quartz clock that can be bonded and integrated to a Si substrate, as described in U.S. Pat. No. 7,459,099.
U.S. Pat. No. 8,151,640 teaches using planar bonding techniques to first integrate a quartz clock resonator on a semiconductor substrate, followed by the integration of a High-Aspect-Ratio Si DRG Resonator on the substrate.